Transportung Horned frog

Well college is out and the time has come for me to make the 6 hour drive home with all of my frogs. What is the best way to transport my Horned frog with out stressing it out too much. Should I just put his terrirum in the back of my car with him it it, or should I put him in a critter keeper with moist paper towels? Any other Ideas? Thanks.